DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.

O-Desmethyltramadol (O-DSMT, desmetramadol) is an opioidanalgesic and an active metabolite which is produced in the liver after the consumption of tramadol.[2] It has little to no history of human usage but is easily accessible through the use of certain online research chemical vendors.

In comparison to tramadol, O-DSMT is reported to be less stimulating and feels considerably closer to a traditional opiate. Being the metabolite that is mainly responsible for the analgesic effect of tramadol, O-DSMT is significantly more potent by weight than its parent compound.

Chemistry

(+/-)O-Desmethyltramadol, or 3-(2-((dimethylamino)methyl)-1-hydroxycyclohexyl)phenol, is an atypical synthetic opioid. O-Desmethyltramadol is loosely analogous to codeine, but is not a morphinan opiate. Instead, it contains two rings including a cyclohexane ring that is bonded to a phenyl ring at R1. This phenyl ring is substituted at R3 with a hydroxy group (OH-). An additional hydroxy group is found at the same location the cyclohexane ring is bonded to at the phenyl ring, R1. O-DMST features a third substitution on its cyclohexane ring at R2. Here the ring is bonded to a dimethylamine group connected through a methylene bridge.

O-Desmethyltramadol is atypical as it is found in a racemate (combination) of its stereoisomers. Stereoisomers are two molecules that share the same chemical structure, but are three-dimensional mirror images of each other. Tramadol is produced as a racemate of its two isomers because the combination is proven to be more effective. Flipping the direction of the R2 and R1 bonds results in the R- and S- enantiomers of O-Desmethyltramadol. O-DMST is nearly identical to tramadol, and is named for the lack of the methyl group of tramadol's R3 methoxy substituion.

Pharmacology

O-DSMT is considerably more potent as a μ-opioidagonist compared to tramadol.[3] Additionally, unlike tramadol, it is a high-affinity ligand of the δ- and κ-opioid receptors.[4]

The two enantiomers of O-DSMT show quite distinct pharmacological profiles;[5] both (+) and (−)-O-DSMT are inactive as serotoninreuptake inhibitors,[6] but (−)-O-DSMT retains activity as a norepinephrinereuptake inhibitor,[7] and so the mix of both the parent compound and metabolites contributes significantly to the complex pharmacological profile of tramadol. While the multiple receptor targets can be beneficial in the treatment of pain (especially complex pain syndromes such as neuropathic pain), it increases the potential for drug interactions compared to other opioids, and may also contribute to side effects.

Opioids exert their effects by binding to and activating the μ-opioidreceptor. This occurs because opioids structurally mimic endogenous endorphins which are naturally found within the body and also work upon the μ-opioid receptor set. The way in which opioids structurally mimic these natural endorphins results in their euphoria, pain relief and anxiolytic effects. This is because endorphins are responsible for reducing pain, causing sleepiness, and feelings of pleasure. They can be released in response to pain, strenuous exercise, orgasm, or general excitement.

Subjective effects

The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWikicontributors. The listed effects should be taken with a grain of salt and will rarely (if ever) occur all at once, but heavier doses will increase the chances and are more likely to induce a full range of effects. Likewise, adverse effects become much more likely on higher doses and may include serious injury or death.

Physical effects

The general sensation of O-DSMT can be described as one of intense euphoria, relaxation, anxiety suppression and pain relief.

Physical euphoria - This particular substance can be considered as less intense in its physical euphoria when compared with that of morphine or diacetylmorphine (heroin). The sensation itself can be described as extreme feelings of intense physical comfort, warmth, love and bliss.

Respiratory depression - At low to moderate doses, this effect results in the sensation that the breath is slowed down mildly to moderately, but does not cause noticeable impairment. At high doses and overdoses, opioid-induced respiratory depression can result in a shortness of breath, abnormal breathing patterns, semi-consciousness, or unconsciousness. Severe overdoses can result in a coma or death without immediate medical attention.

Cognitive effects

Cognitive euphoria - This particular substance can be considered as less intense in its cognitive euphoria when compared with that of morphine or diacetylmorphine (heroin). The sensation itself can be described as powerful and overwhelming feeling of emotional bliss, contentment, and happiness.

Toxicity and harm potential

O-DSMT has a moderate potential toxicity relative to its dose due to its potency. As with all opioids, long-term effects can vary but can include diminished libido, apathy and memory loss. It is also potentially lethal when mixed with depressants like alcohol or benzodiazepines.

O-DSMT has recently been marketed as a currently legal substitute for illegal opioid drugs, either in powder form or mixed into various other preparations. One such blend was sold under the brand Krypton and contains powdered kratom leaf (Mitragyna speciosa) laced with O-DSMT and was reportedly linked to at least 9 accidental deaths from overdose during 2010–2011.[8][9][10]

Tolerance and addiction potential

As with other opioids, the chronic use of O-DSMT can be considered moderately addictive with a high potential for abuse and is capable of causing psychological dependence among certain users. When addiction has developed, cravings and withdrawal symptoms may occur if a person suddenly stops their usage.

Tolerance to many of the effects of O-DSMT develops with prolonged and repeated use. The rate at which this occurs develops at different rates for different effects, with tolerance to the constipation-inducing effects developing particularly slowly for instance. This results in users having to administer increasingly large doses to achieve the same effects. After that, it takes about 3 - 7 days for the tolerance to be reduced to half and 1 - 2 weeks to be back at baseline (in the absence of further consumption). O-DSMT presents cross-tolerance with all other opioids, meaning that after the consumption of O-DSMT all opioids will have a reduced effect.

Dangerous interactions

Although many drugs are safe on their own, they can become dangerous and even life-threatening when combined with other substances. The list below contains some common potentially dangerous combinations, but may not include all of them. Certain combinations may be safe in low doses of each but still increase the potential risk of death. Independent research should always be done to ensure that a combination of two or more substances is safe before consumption.

Dissociatives - This combination can result in an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.

Stimulants - It is dangerous to combine O-DSMT, a depressant, with stimulants due to the risk of excessive intoxication. Stimulants decrease the sedative effect of O-DSMT, which is the main factor most people consider when determining their level of intoxication. Once the stimulant wears off, the effects of O-DSMT will be significantly increased, leading to intensified disinhibition as well as other effects. If combined, one should strictly limit themselves to only taking a certain amount of O-DSMT.